[PATCH v3] LSM: use 32 bit compatible data types in LSM syscalls.

[Paul Moore]

On Wed, Mar 13, 2024 at 4:07 PM Paul Moore <paul at paul-moore.com> wrote:
> On Mar 13, 2024 Casey Schaufler <casey at schaufler-ca.com> wrote:
> >
> > LSM: use 32 bit compatible data types in LSM syscalls.
> >
> > Change the size parameters in lsm_list_modules(), lsm_set_self_attr()
> > and lsm_get_self_attr() from size_t to u32. This avoids the need to
> > have different interfaces for 32 and 64 bit systems.
> >
> > Cc: stable at vger.kernel.org
> > Fixes: a04a1198088a: ("LSM: syscalls for current process attributes")
> > Fixes: ad4aff9ec25f: ("LSM: Create lsm_list_modules system call")
> > Signed-off-by: Casey Schaufler <casey at schaufler-ca.com>
> > Reported-and-reviewed-by: Dmitry V. Levin <ldv at strace.io>
> > ---
> >  include/linux/lsm_hook_defs.h                        |  4 ++--
> >  include/linux/security.h                             |  8 ++++----
> >  security/apparmor/lsm.c                              |  4 ++--
> >  security/lsm_syscalls.c                              | 10 +++++-----
> >  security/security.c                                  | 12 ++++++------
> >  security/selinux/hooks.c                             |  4 ++--
> >  security/smack/smack_lsm.c                           |  4 ++--
> >  tools/testing/selftests/lsm/common.h                 |  6 +++---
> >  tools/testing/selftests/lsm/lsm_get_self_attr_test.c | 10 +++++-----
> >  tools/testing/selftests/lsm/lsm_list_modules_test.c  |  8 ++++----
> >  tools/testing/selftests/lsm/lsm_set_self_attr_test.c |  6 +++---
> >  11 files changed, 38 insertions(+), 38 deletions(-)
>
> Okay, this looks better, I'm going to merge this into lsm/stable-6.9
> and put it through the usual automated testing as well as a kselftest
> run to make sure everything there is still okay.  Assuming all goes
> well and no one raises any objections, I'll likely send this up to
> Linus tomorrow.

I had to squash the code snippet below into the patch to address a
build problem identified by the kernel build robot.  I'm going to keep
Casey's sign-off and Dmitry's reported-reviewed tag as I feel this
change is minor, but if anyone has any objections please let me know
soon.

[NOTE: cut-n-paste'd into email, likely whitespace damage, but you get the idea]

diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index 77eb9b0e7685..e619ac10cd23 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -960,10 +960,10 @@ asmlinkage long sys_cachestat(unsigned int fd,
               struct cachestat __user *cstat, unsigned int flags);
asmlinkage long sys_map_shadow_stack(unsigned long addr, unsigned long size, un
signed int flags);
asmlinkage long sys_lsm_get_self_attr(unsigned int attr, struct lsm_ctx *ctx,
-                                     size_t *size, __u32 flags);
+                                     u32 *size, u32 flags);
asmlinkage long sys_lsm_set_self_attr(unsigned int attr, struct lsm_ctx *ctx,
-                                     size_t size, __u32 flags);
-asmlinkage long sys_lsm_list_modules(u64 *ids, size_t *size, u32 flags);
+                                     u32 size, u32 flags);
+asmlinkage long sys_lsm_list_modules(u64 *ids, u32 *size, u32 flags);

/*
 * Architecture-specific system calls

-- 
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